The proposed research investigates the application of ultrasonic, vibrational energy to a hemodialyzer membrane and its effect on mas transfer during hemodialysis. Two physical phenomena are expected to play a part in improving mass transfer: acoustic streaming and dissipation of the protein gel layer. Acoustic streaming refers to enhanced transfer due to microscopic vortices induced by acoustic waves. The protein el layer is a thin layer of protein and blood components that is driven against the dialyzer membrane by the convection inherent in dialysis. This proposal predicts that this layer can be dissipated by vibrational energy, thereby reducing the resistance to solute transfer across the "effective membrane". Both these phenomena will act to improve clearance, and enhance the efficacy of dialysis therapy. During Phase I, laboratory testing is proposed select a configuration optimized for improved clearance. A device will be designed and constructed, and further in vitro testing will be performed to assess improvements in dialysis efficacy that could be realized by employing such a device. Phase II will involve the refinement of the device for human use and clinical trials performed in vivo using clearance measurement of substances of interest to the dialysis community as the measure of efficacy. PROPOSED COMMERCIAL APPLICATIONS: The successful application of this technology can either be sold directly to dialysis service providers as a stand alone medical device for use with any dialysis monitor, or it can be licensed or sold to dialysis equipment manufacturers for incorporation in their monitors.